Here are a few shots of actor Jack Lemmon from the LIFE archives. Lemmon played many sack-suited characters throughout the Ivy heyday. He’s pictured on the set of “The Apartment” in 1959 in a classic outfit formula you should try if you haven’t. You take a simple solid suit and tie (often a knit), and for subtle flair, a white shirt with a pinned club collar. Everything is nondescript save for a little conservative dash up at the neck.
Below, at a pre-Oscars party in 1960, with Dean Martin on the left:
And with Walter Matthau in 1966. — CC